Patent ES-8601432-A1 (ES)
Title: Flexible power transmission belt and power transmission system.
IPC: F16G1/28
Filed: 1984-10-31
Abstract: The flexible power transmission belt has teeth (13) with cavity sections between. Each tooth is longitudinally symmetrical in cross-section about a centre line (X-X). Each tooth has a root (30,31), a tip (25-27) and oppositely convex flanks (21,22). - The belt tooth root is defined by first and second arcs (30,31) and the belt cavity has a base connecting the arcs of adjacent teeth. The cavity base has a plane coinciding with a belt land line (L) colinear with the bases of all of the cavities. Each opposite flank is formed of a curve (21,22) which approximates the centre of an arc of a circle whose centre lies on the land line. (2/5) EPAB- EP-106694 B A flexible power transmission belt haVing a plurality of teeth (13), said belt teeth being separated by belt cavity portions, each belt tooth in longitudinal cross-section being symmetrical about a belt tooth centre line (X-X), said belt tooth including a root portion (30,31), a tip portion (25 to 27) and opposite convex arcuate flank portions (21,22) extending from said tip portion, each said belt cavity portion being symmetrical about a belt cavity centre line, said belt tooth root portion being defined at least partly by first and second arcs (30,31) approximating the arc of a circle on opposite sides of said belt tooth centre line extending into the corresponding flank portions (21,22) of the belt tooth and said belt cavity having a base portion (32) connecting said first arc of each tooth with said second arc of thene xt consecutive tooth, said base portion which is longitudinal cross-section is a line coinciding with a belt land line (L) which is colinear with base portions of other belt cavities on said belt, said belt tooth having a height dimension (H) measured between the extremity of said tooth tip portion and said belt land line (L) and having a width dimension (W) measured between said opposite flank portions along a line parallel to such belt land line and including the points (A,C) at which said first and second arcs intersect said flank portions, said belt tooth having a height to width relation within a first predetermined range, each said opposite flank portion being formed of a curve (21,22) which approximates the arc of a circle whose centre of curvature (23,24) lies substantially on said belt land line on tbe side of the belt tooth centre line which is opposite that of the flank portion in question and which curve is such that a tangent line (T) drawn to it at the point thereon (J,K) which is at a distance from the belt land line (L) equal to 0.3 times the width dimension (W) of the belt tooth forms an angle (a) with respect to the tooth centre - EP-106694 B A flexible power transmission belt haVing a plurality of teeth (13), said belt teeth being separated by belt cavity portions, each belt tooth in longitudinal cross-section being symmetrical about a belt tooth centre line (X-X), said belt tooth including a root portion (30,31), a tip portion (25 to 27) and opposite convex arcuate flank portions (21,22) extending from said tip portion, each said belt cavity portion being symmetrical about a belt cavity centre line, said belt tooth root portion being defined at least partly by first and second arcs (30,31) approximating the arc of a circle on opposite sides of said belt tooth centre line extending into the corresponding flank portions (21,22) of the belt tooth and said belt cavity having a base portion (32) connecting said first arc of each tooth with said second arc of thene xt consecutive tooth, said base portion which is longitudinal cross-section is a line coinciding with a belt land line (L) which is colinear with base portions of other belt cavities on said belt, said belt tooth having a height dimension (H) measured between the extremity of said tooth tip portion and said belt land line (L) and having a width dimension (W) measured between said opposite flank portions along a line parallel to such belt land line and including the points (A,C) at which said first and second arcs intersect said flank portions, said belt tooth having a height to width relation within a first predetermined range, each said opposite flank portion being formed of a curve (21,22) which approximates the arc of a circle whose centre of curvature (23,24) lies substantially on said belt land line on tbe side of the belt tooth centre line which is opposite that of the flank portion in question and which curve is such that a tangent line (T) drawn to it at the point thereon (J,K) which is at a distance from the belt land line (L) equal to 0.3 times the width dimension (W) of the belt tooth forms an angle (a) with respect to the tooth centre USAB- US4515577 A The flexible power transmission belt has teeth, each of which has a pair of arcuate convex flank portions which in longitudinal cross-section, closely approximate to an arc of a circle. Each tooth exhibits a height to width relationship within a predetermined range, and the arcuate flanks each have a pressure angle within a predetermined range. - The belt is used in combination with a toothed pulley whose teeth are conjugate to the belt teeth and whose cavities between the teeth have a height to width relationship with another predetermined range and have concave flanks exhibiting a pressure angle in still another predetermined range. The belt tooth width is approximately 0.98 of the pulley cavity width.